Cigarette smoking is a vitally important public health problem. It is a major contributor to cardiovascular disease and one of the leading causes of cancer and respiratory disease. Research in primary care over the last two decades has indicated that smoking cessation interventions in medical settings can be effective. However, there have been few published reports of research examining the effectiveness of smoking cessation interventions in hospital settings. In-patient smoking cessation interventions can potentially reach a large number of smokers. A hospital stay can also be an effective "teachable moment" for smoking cessation advice. Smoking bans in place in hospitals make it a time of enforced abstinence and, therefore, an opportunity to overcome the symptoms of physical addiction. Patients are removed from their usual environmental cues for smoking, making initial cessation easier, and they might be particularly receptive to preventive health messages at a time of ill-health. Finally, there is increased access to health care providers whom patients see as valid and knowledgeable sources of health information. The proposed project experimentally tests methods to promote long-term smoking cessation in hospitalized patients. All smokers admitted to three hospitals over a 27- month period will be identified as part of the admissions process. Those who meet eligibility requirements (n=4l77) will be randomly assigned to one of three treatment conditions: minimal care; a low intensity intervention whose centerpiece is brief firm advice by health care providers and labelling of the smokers' charts (PA intervention); and the PA intervention plus more intensive counseling and follow-up after discharge performed by a research nurse (PA+NC intervention). Intervention components include provision of smoking cessation manuals and training of health care providers (all conditions); structural reminders to health care providers to give smoking cessation advice and provision of smoking cessation advice by a variety of health care providers on several different occasions (PA and PA+NC); and in-hospital counseling that is tailored to patient characteristics, feedback about a biological marker of smoking, a stepped care approach, and follow-up telephone counseling after discharge (PA+NC only). All participants will be followed for l2 months after discharge from the hospital to examine the relative effectiveness and cost-effectiveness of the smoking cessation programs. In addition, information about smoking cessation advice given to study patients by primary care physicians in the 12 months after discharge from hospital will be gathered to assess the possible synergistic effects of advice provided in in-patient and out-patient settings.